| 摘要 |
The invention concerns a vessel-puncturing cannula comprising a needle which has a bevelled tip with an inlet opening, the needle further having a mounted cannula holder. Since the position of the blood vessels cannot always be detected from the exterior, when puncturing is carried out it is difficult to determine the puncture angle and puncture depth before the cannula is inserted and a high degree of sensitivity and experience is required. With the known cannulae, incorrect puncturing can result in the blood vessel being perforated, or the cannula penetrating the vessel wall only partially, or a subsequently introduced guide wire causing lesions. The object of the invention is to provide a vessel-puncturing cannula by means of which the puncture cannula can easily be placed with its inlet opening in an optimum position which can be indicated reliably by means of the blood flow. Furthermore, injury to the surrounding tissue, vessels and nerves should be avoided as far as possible. This object is achieved by a cannula whose inlet opening is greatly reduced with respect to the inlet openings of conventional cannulae, with a conical tip and a guide wire deflection surface disposed in the region of the inlet opening. |
